Enabling High-power UE Transmission

ABSTRACT

Systems and methods are disclosed for permitting higher transmit power at a mobile device. In one embodiment, a method is disclosed, comprising: receiving, at a base station, an emergency request from a mobile device; sending, from the base station to a neighboring base station, a high power reservation message to reserve one or more radio resource blocks at the neighboring base station for non-use; and sending, from the base station to the mobile device, a resource allocation including the one or more radio resource blocks and a power control message requesting high transmit power.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of, and claims the benefit of anearlier filing date under 35 USC 120 based on, U.S. patent applicationSer. No. 15/716,428, having attorney docket no. PWS-71780US02, filedSep. 26, 2017, entitled “Enabling High-Power UE Transmission,” whichitself is a continuation of, and claims the benefit of an earlier filingdate under 35 USC 120 based on, U.S. patent application Ser. No.14/868,074, having attorney docket no. PWS-71780US01, filed Sep. 26,2015, entitled “Enabling High-Power UE Transmission,” , U.S. Pat. No.9,775,017, which itself claims the benefit of priority under 35 USC119(e) to U.S. Provisional Patent Application No. 62/056,455, entitled“Enabling High-Power UE Transmission,” filed on Sep. 26, 2014 withdocket number PWS-71780U500, each of which are hereby incorporated byreference in their entirety for all purposes. In addition, thisapplication incorporates the following applications by reference intheir entirety: U.S. patent application Ser. No. 13/889,631, entitled“Heterogeneous Mesh Network and a Multi-RAT Node Used Therein,” filed onMay 8, 2013; U.S. patent application Ser. No. No. 14/034,915, entitled“Dynamic Multi-Access Wireless Network Virtualization,” filed on Sep.23, 2013; U.S. patent application Ser. No. 14/183,176, entitled “Methodsof Incorporating an Ad Hoc Cellular Network into a Fixed CellularNetwork,” filed Feb. 18, 2014; U.S. patent application Ser. No.14/024,717, entitled “Heterogeneous Self-Organizing Network for Accessand Backhaul,” and filed on Sep. 12, 2013; U.S. patent application Ser.No. 14/146,857, entitled “Heterogeneous Self-Organizing Network forAccess and Backhaul,” and filed on Jan. 3, 2014; and U.S. patentapplication Ser. No. 14/571,250, entitled “Virtualization of the EvolvedPacket Core to Create a Local EPC,” filed on Dec. 15, 2014.

BACKGROUND

Small cells and mobile base stations are being considered for manyapplications, including first responder and public safety applications.These cells are capable of bringing LTE access directly to the site of adisaster or emergency, as described in U.S. patent application Ser. No.14/183,176, which is hereby incorporated by reference for all purposes.However, it is well-known that many LTE bands are at high frequencies,such as 1900 MHz, 2400 MHz, or even higher. As higher frequencies haveworse penetration with more attenuation, these small base stations havethe problem that even when deployed to the site, they may not be able toprovide access and coverage areas deep into buildings or into basements.As well, when buildings are on fire or when buildings are collapsing, itis conceivable that the people who need to make emergency calls will bein the interior of such buildings. Further, when a building is on fire,the residents inside need to reach as wide a coverage area as they canto seek emergency support. To support scenarios like these, high-powertransmission from the user equipment (UE) may be enabled.

A need therefore exists to provide improved quality of radio coverage tothose emergency users.

SUMMARY

Systems and methods are disclosed for permitting higher transmit powerat a mobile device. In one embodiment, a method is disclosed,comprising: receiving, at a base station, an emergency request from amobile device; sending, from the base station to a neighboring basestation, a high power reservation message to reserve one or more radioresource blocks at the neighboring base station for non-use; andsending, from the base station to the mobile device, a resourceallocation including the one or more radio resource blocks and a powercontrol message requesting high transmit power.

The method may further comprise identifying whether the emergencyrequest may be an emergency call request or indicates emergency status.The method may further comprise identifying radio resources based onusage of radio resources by nearby mobile devices, nearby base stations,or both. The method may further comprise coordinating scheduling with acoordinating node via an X2 protocol message.

The base station may be an eNodeB, the mobile device may be a userequipment (UE), and the high power reservation message may be a HighInterference Indicator (HII) message communicated via an X2 protocolmessage. The high power reservation message may comprise a HighInterference Indicator (HII) message and a Relative Narrowband TransmitPower (RNTP) message. The emergency request may be an emergency attachrequest without user equipment device authentication. The emergencyrequest may be a request to make an emergency call. The power controlmessage identifies the one or more radio resource blocks. The one ormore radio resource blocks are resource blocks designated by frequencyor time. The mobile device may be directed to use its maximum transmitpower for uplink transmission to the base station. The base station mayuse a higher transmit power for downlink transmission to the mobiledevice.

In another embodiment, a base station is disclosed, comprising: aprocessing module for providing wireless communications to mobile users;a core network interface coupled to the processing module and incommunication with a core network; and an access interface coupled tothe processing module, in communication with one or more mobile devices,and capable of being used for emergency communications by the one ormore mobile devices; wherein the processing module may be configured to:receive, at the base station, an emergency request from a mobile device;send, from the base station to a neighboring base station, a high powerreservation message to reserve one or more radio resource blocks at theneighboring base station for non-use; and send, from the base station tothe mobile device, a resource allocation including the one or more radioresource blocks and a power control message requesting high transmitpower.

The base station may be an eNodeB, the mobile device may be a userequipment (UE), and the high power reservation message may be a HighInterference Indicator (HII) message communicated via an X2 protocolmessage. The high power reservation message may comprise a HighInterference Indicator (HII) message and a Relative Narrowband TransmitPower (RNTP) message. The emergency request may be an emergency attachrequest without user equipment device authentication. The emergencyrequest may be a request to make an emergency call. The power controlmessage identifies the one or more radio resource blocks. The one ormore radio resource blocks are resource blocks designated by frequencyor time. The mobile device may be directed to use its maximum transmitpower for uplink transmission to the base station.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a deployment scenario, in accordancewith some embodiments.

FIG. 2 is a flowchart of an emergency call coordination process, inaccordance with some embodiments.

FIG. 3 is a schematic diagram of an enhanced base station, in accordancewith some embodiments.

FIG. 4 is a schematic diagram of a coordination node, in accordance withsome embodiments.

DETAILED DESCRIPTION

As mentioned above, a need exists to provide improved quality of radiocoverage to those emergency users.

One way to improve service to emergency users is to permit them to usehigher power when making an emergency call. However, such high-powertransmission could cause unintended or adverse consequences, such asunacceptable levels of uplink interference. This negative impact can beresolved using interference coordination between base stations in thenetwork, as described below.

The 3GPP LTE standard contemplates inter-cell interference cancellation,or ICIC. Typically, eNodeBs exchange interference information of theircells with the neighbor eNBs by sending an X2 message (Load Informationmessage3) after each ICIC period. At this time, the message includesinformation like Relative Narrowband Transmit Power (RNTP),High-Interference Indicator (HII), and Overload Indicator (OI).

The RNTP message indicates the frequency resources (RBs) that will beusing high transmit power for downlink during the next ICIC period.Power strength of each RB is measured over the current ICIC period andshown in bits (0: low, 1: high). For example, the strength can beaveraged over the current ICIC period.

The HII message indicates frequency resources (RBs) that will be usinghigh Tx power for UL during the next ICIC period, just like RNTP, butfor UL this time. RBs with high allocated power are used by UEs at celledges, and thus are very likely to cause interference for neighborcells. The power strength of each RB is measured and shown in bits (0:low, 1: high).

RNTP and HII are information about interference to be caused by a cellto its neighbor cell. However, as OI is information about interferencethat has already been caused by the neighbor cell to the cell during thelast ICIC period, it is not contemplated here.

ICIC may include the following operations: generating interferenceinformation (ICIC period #11), wherein Cell A and B measuresignal/interference strength during an ICIC period, and generateinterference information (RNTP, HII, OI); sharing interferenceinformation (ICIC period #12), wherein Cell A and B share theinterference information with neighbor cells through X2 message, andwherein the X2 delay between neighbor cells must be shorter than theICIC period; resource coordination: ICIC calculation (ICIC period #12),wherein both cells and, in some embodiments, a coordinating node, run anICIC algorithm based on the neighbor cell's interference informationreceived, and determine frequency resources (RBs or sub-carriers) thatwill be used at cell edges, and thus will be using high Tx power; andcoordinating resource-based local scheduling (ICIC period #13). Theresults of ICIC calculation are applied to one or more schedulerslocated at cell A, cell B, and/or other schedulers. Based on coordinatedresources, cells perform local scheduling (i.e. allocating radioresources to the UEs accessed to them) depending on the channel statusof each UE.

In some embodiments, the UE may initiate an emergency call request. Inresponse to the UE's emergency call request, the eNodeB to which it isattached, which may be a multi-radio access technology (multi-RAT)mobile wireless mesh base station, may be enabled to work with acoordination node incorporating a scheduler, which may be part of aself-organizing network (SON) module. The SON module may choose specificuplink radio blocks/physical resource blocks (PRBs) that will cause theleast uplink interference to adjacent eNodeBs, and send these blocks tothe UE. The SON module may also permit the UE to use high transmissionpower to this UE for this emergent call.

In anticipating the potential uplink interference effect introduced bythis call, the coordinating node, which may also be an X2 aggregationpoint, can use X2 interfaces to send the High Interference Indicator(HII) message to related eNodeBs or neighbor eNodeBs, including thespecific PRBs that were assigned. With the receipt of these HIImessages, the eNodeBs that have been notified will exclude the PRBs asindicated in the HII messages from use, thus avoiding unnecessary uplinkinterference.

FIG. 1 is a schematic diagram of a deployment scenario, in accordancewith some embodiments. Emergency vehicle 101 has an in-vehicle basestation 102 connected via wireless backhaul 104 to macro cell 103. Alsonearby is neighboring small cell 105. Emergency vehicle 101 is on itsway to disaster site 107, where it will permit mobile devices to attach,such as UE 108, held by a mobile user. Dotted lines representundesirable interference, and solid lines represent desired signal. Asshown, both macro cell 103 and 105 generate uplink and downlinkinterference to UE 106, and vice versa. The desired signal is between UE106 and emergency vehicle base station 102.

As shown, the coverage area of macro cell 103 includes in-vehicle basestation 102, which uses this coverage to obtain wireless backhaulconnection 104. However, although macro cell 103 does not have coverageof UE 106, it may still interfere, in some embodiments. Likewise, smallcell 105 does not have an overlapping coverage area but may stillinterfere as well.

Disaster site 107 is shown as a building, and UE 106. It is well-knownthat the propagation of radio waves is negatively impacted by buildingwalls, and that signal attenuation increases as higher-frequency bandsare used. For example, a 700 MHz signal may penetrate a building well,but a 1900 MHz signal or 2.4 GHz signal, as may be used for PCS/LTE andWi-Fi, respectively, will not penetrate the building well. However, asemergency vehicle 101 is outside the building, and as emergency vehicle101 also does not have the electrical power or physical size needed tobroadcast a strong signal, it is important to enable the UE to transmitwith a strong signal and for the UE not to be subject to interferenceduring its transmission.

Operation of the components shown in FIG. 1 may occur as follows, insome embodiments. Mobile base station 102 may permit UE 106 to attach,or may receive an emergency attach request. Mobile base station 102 mayalso be informed of, either directly by sampling/sniffing its localradio environment or indirectly via means of UE measurement reports orself-organizing network (SON) coordination messages from a coordinationserver (not shown), sources of interference in its neighborhood, herebeing macro cell 103 and small cell 105. Once mobile base station 102receives an emergency attach request or emergency call request from UE106, it may identify the emergency status of the call, identify a radioresource such as a resource block that should be used by the UE, andsend a high interference indicator (HII), a relative narrowband transmitpower (RNTP) message, or both to each of macro cell 103 and small cell105. This may be via a coordination server (not shown). The base station102 may then inform UE 106 that it should use the designated radioresources, and that it should use a higher transmit power. This mayresult in improved quality of service for UE 106.

In some embodiments, the following conditions may apply. Mobile user 108may be indoors and may have a UE with ordinary or low power. In-vehiclebase station 102 may have a limited power budget and may broadcast asignal that does not propagate inside of the building. In some cases acell coverage pattern may include small cell overlay and macro cellunderlay, as shown in FIG. 1, and some or all of the neighboring cellsmay be caused not to interfere using X2 protocol messages. However, thesystems and methods disclosed herein apply also to any conditions,regardless of whether these conditions apply.

FIG. 2 is a flowchart of an emergency call coordination process, inaccordance with some embodiments. At step 201, a base station receivesan incoming call. This may be via an emergency attach message accordingto the LTE protocol. Alternately, it may be a circuit-switched call to adesignated emergency number, such as 911 in the U.S., or acircuit-switched fallback call, or a voice over LTE (VoLTE) call, or aninternet multimedia system (IMS) call, or a combination of the above.

At step 202, the base station attempts to determine whether the call isan emergency call. If the call is identified as an emergency call, thefollowing steps may be performed. Identification of the call as anemergency call may occur in different ways. For example, an LTE UE maysubmit an emergency attach message to signal that it is attempting toattach to the network without authentication to place an emergency call.The attach message may indicate that it is an emergency attach.Alternately, a UE may attempt to attach without authenticating, whichmay be treated as an emergency attach. Alternately, an attach may berequested by a UE to a particular network that is a known emergencynetwork. Alternately, a call may be initiated by an authenticated orattached UE that indicates that it is an emergency call. Alternately, anLTE UE may attempt a VoLTE emergency call, or an IMS emergency call. Insome embodiments an emergency call may be identified using one or moreof matching of the destination number, the destination packet gateway(PGW), the destination call session control function (CSCF), therequested quality of service, or any other special emergency flag in therequest. Certain mobile devices may be given emergency call status forany call made on the device. It is understood that many methods foridentifying emergency calls are understood, and each method would beequivalent to these methods, particularly if able to be performed atthis stage.

At step 203, resources may be identified for higher-power transmissionby the UE (uplink) as well as the base station (downlink). Theseresources may be time slots, frequency slots, resource blocks, or otherresources such as are typically scheduled for uplink or downlinkcommunications. These resources may be identified at a scheduler in thebase station, a scheduler in a remote location (such as a baseband unitremotely located from a base station radio head), or in another type ofscheduler. However, to meet the latency requirements of thisapplication, a scheduler in the base station is preferred to beinvolved. The UE will use these identified resources to, for example,transmit at a higher power than is otherwise permitted. The highertransmit power may be higher power than any other UE. The higher powermay be selected based on the radio frequency interference in theappropriate resource block, with consideration given to interferencecoordination with other cells (see below) and also to non-coordinatedinterference, such as path loss, other emission sources, building walls,foliage, or other interference.

As described in the preceding paragraph, resources may be identified forboth receive and transmit, for both downlink and uplink. In someembodiments, high-power UE transmissions will be cleared using an HIImessage, and high-power base station transmissions will be cleared usingan RNTP message. In some embodiments, high power may be used for one ofthe two links (e.g., UL only or DL only).

At step 204, the base station performs coordination steps to coordinateinterference between cells, i.e., inter-cell interference coordination(ICIC). ICIC may be performed by the base station sending X2 protocolmessages to other eNodeBs in the area.

Starting in 3GPP Release 8, ICIC involves generating interferenceinformation for each resource block, and exchanging this informationwith neighboring base stations through X2 messages, including a LoadInformation message that indicates what radio resources are subject toload and/or interference.

In some embodiments, the base station may send one or both of a RelativeNarrowband Transmit Power (RNTP) and a High Interference Indicator (HII)to its neighboring base stations using X2 messages. The RNTP and HIImessages may be used to protect the resources identified in step 203 forcommunication with the UE making the emergency call, on the downlink anduplink, respectively. One or both of RNTP and HII may be used forcoordination. However, it is noted that both RNTP and HII should be usedto provide improved service on both the uplink and downlink.

In some embodiments, one or both of ICIC and enhanced ICIC (eICIC) maybe used. eICIC permits resource block allocation and interferencecoordination in the time domain, which can be combined with coordinationin the frequency domain via ICIC.

At step 205, the base station may coordinate with one or more remoteschedulers. This step is optional in some embodiments. In someembodiments, ICIC may be performed in conjunction with a coordinationnode that is responsible for coordinating multiple eNodeBs or basestations. The ICIC coordination may take the form of X2 messages thatcontain scheduling hints. The scheduling hints may involve one or moreschedulers explicitly assigning particular resource blocks to particularUEs. The scheduling hints may involve information about transmit power,interference, signal quality, network congestion, handover prediction,interference prediction, or other information that may apply to one ormore base stations coordinated by the coordination node.

At step 206, the resources identified in step 203 are transmitted to theUE, via normal channels, such as using a regularly-scheduled LTEphysical downlink control channel (PDCCH) for downlink resources. AsICIC scheduling information is transmitted every tens to hundreds ofmilliseconds for LTE protocol systems, the latency budget for performingsteps 201-206 may be within this timeframe. Ideally, the latency budgetmay be as close as possible to, or less than, a single scheduling periodor transmission time interval (TTI), 1 ms.

In some embodiments, the base station may be a mobile base station beingdeployed to a disaster site. For instance, a mobile base station mayarrive on the scene while a widespread emergency is still going on. Insuch situations, calls that are not emergency calls, such as ordinaryvoice calls, or any and all calls may be identified as emergency callsand given permission to use higher transmit power.

In some embodiments, public safety communications using a designatedband, such as LTE Band 14 in the U.S., may receive preferentialtreatment as if they were emergency calls according to the methodsdescribed herein. This ensures that public safety personnel are able toperform their duties and communicate effectively with each other evenwhen they are relying on a low-power mobile base station.

In some embodiments, the disclosed systems and methods may coexist withother services that are offered to facilitate emergency calling, such aslocation identification of the UE, prioritized quality of service,prioritized use of signaling channels, prioritized routing, or otheremergency calling methods.

In some embodiments, a large number of UEs may attempt to attach to abase station as emergency UEs. For example, if a mobile base station isthe only base station nearby at a disaster scene, many UEs may attemptto connect to the mobile base station. The mobile base station may usethe systems and methods disclosed herein to provide priority access toemergency calls to the extent possible. For example, the mobile basestation may declare, using HII and RNTP messages, that several or allavailable resource blocks will be needed for emergency calling. In someembodiments, guard bands may be included as well, so that HII and RNTPmay be used to reserve additional blocks on either side of a user'stransmission.

FIG. 3 is a schematic diagram of a mesh network base station, inaccordance with some embodiments. Mesh network base station 300 mayinclude processor 302, processor memory 304 in communication with theprocessor, baseband processor 306, and baseband processor memory 308 incommunication with the baseband processor. Base station 300 may alsoinclude first radio transceiver 310 and second radio transceiver 312,internal universal serial bus (USB) port 316, and subscriber informationmodule card (SIM card) 318 coupled to USB port 314. In some embodiments,the second radio transceiver 312 itself may be coupled to USB port 316,and communications from the baseband processor may be passed through USBport 316.

A virtualization layer 330 may also be included for mediatingcommunications with an evolved packet core EPC, specifically includingthe core network EPC (not shown) and local evolved packet core (EPC)module 320. Local EPC 320 may be used for authenticating users andperforming other EPC-dependent functions when no backhaul link isavailable. A scheduler module 322 may also be coupled to processor 302.The scheduler may be used for UEs connected to the base station, and insome cases may additionally be in communication with a coordinationserver, such as the one shown in FIG. 4, to perform scheduling and ICICfunctions. Virtualization layer 330, local EPC 320, and scheduler 322may each run on processor 302 or on another processor, or may be locatedwithin another device.

Processor 302 and baseband processor 306 are in communication with oneanother. Processor 302 may perform routing functions, and may determineif/when a switch in network configuration is needed. Baseband processor306 may generate and receive radio signals for both radio transceivers310 and 312, based on instructions from processor 302. In someembodiments, processors 302 and 306 may be on the same physical logicboard. In other embodiments, they may be on separate logic boards.

The first radio transceiver 310 may be a radio transceiver capable ofproviding LTE eNodeB functionality, and may be capable of higher powerand multi-channel OFDMA. The second radio transceiver 312 may be a radiotransceiver capable of providing LTE UE functionality. Both transceivers310 and 312 are capable of receiving and transmitting on one or more LTEbands. In some embodiments, either or both of transceivers 310 and 312may be capable of providing both LTE eNodeB and LTE UE functionality.Transceiver 310 may be coupled to processor 302 via a PeripheralComponent Interconnect-Express (PCI-E) bus, and/or via a daughtercard.As transceiver 312 is for providing LTE UE functionality, in effectemulating a user equipment, it may be connected via the same ordifferent PCI-E bus, or by a USB bus, and may also be coupled to SIMcard 318.

SIM card 318 may provide information required for authenticating thesimulated UE to the evolved packet core (EPC). When no access to anoperator EPC is available, local EPC 320 may be used, or another localEPC on the network may be used. This information may be stored withinthe SIM card, and may include one or more of an international mobileequipment identity (IMEI), international mobile subscriber identity(IMSI), or other parameter needed to identify a UE. Special parametersmay also be stored in the SIM card or provided by the processor duringprocessing to identify to a target eNodeB that device 300 is not anordinary UE but instead is a special UE for providing backhaul to device300.

Wired backhaul or wireless backhaul may be used to connect to a corenetwork as well as to a coordination server, in some embodiments. Wiredbackhaul may be an Ethernet-based backhaul (including Gigabit Ethernet),or a fiber-optic backhaul connection, or a cable-based backhaulconnection, in some embodiments. Additionally, wireless backhaul may beprovided in addition to wireless transceivers 310 and 312, which may beWi-Fi 802.11a/b/g/n/ac/ad/ah, Bluetooth, ZigBee, microwave (includingline-of-sight microwave), or another wireless backhaul connection. Anyof the wired and wireless connections may be used for either access orbackhaul, according to identified network conditions and needs, and maybe under the control of processor 302 for reconfiguration.

Other elements and/or modules may also be included, such as a homeeNodeB, a local gateway (LGW), a self-organizing network (SON) module,or another module. Additional radio amplifiers, radio transceiversand/or wired network connections may also be included.

Processor 302 may identify the appropriate network configuration, andmay perform routing of packets from one network interface to anotheraccordingly. Processor 302 may use memory 304, in particular to store arouting table to be used for routing packets. Baseband processor 306 mayperform operations to generate the radio frequency signals fortransmission or retransmission by both transceivers 310 and 312.Baseband processor 306 may also perform operations to decode signalsreceived by transceivers 310 and 312. Baseband processor 306 may usememory 308 to perform these tasks.

FIG. 4 is a schematic diagram of a coordination server in a Long TermEvolution (LTE) architecture, in accordance with some embodiments.Coordination server 401 provides services to, and is coupled to, eNodeB402 and eNodeB 403, on a RAN side of a network (i.e., inside of thegateway). Coordination server 401 provides services to, and is coupledto, MME 404, macro eNodeB 405, and macro eNodeB 406, on a core networkside of the network (outside of the gateway). Coordination server 401corresponds to LAC 110, in some embodiments.

Within coordination server 401 are self-organizing network (SON) module411, containing neighbor relation table (NRT) 412 and UE measurementreport processing module 413; evolved packet core (EPC) module 421,containing EPC finite state machine module 422 and macro eNodeB table423; radio access network (RAN) module 431, containing eNodeB finitestate machine module 432 and eNodeB table 434; and user equipment (UE)module 441, containing UE finite state machine module 442 and S1/X2handover mapping table 443. In some embodiments, SON module 411 mayperform NRT maintenance, load information processing and fractionalfrequency reuse (FFR) processing; RAN module 431 may perform X2association management with eNodeBs 402, 403; EPC module 421 may performX2 association management with macro eNodeBs 405, 406; and UE module mayperform X2 handover and S1/X2 translation between eNodeBs 402, 403 andmacro eNodeBs 405, 406. Finite state machine modules 422, 432, 442 mayinclude one or more states for modeling the operational state of aconnected EPC, UE, or RAN, respectively. More than one FSM may bepresent at each of modules 421, 431, 441, so that coordination server401 may be enabled to model the operational state of several networknodes at once. All the above managers/modules interact with each otherto accomplish the assigned functionality.

In some embodiments, coordination server 401 may include one or moreprocessors, each with one or more processor cores. Each of modules 411,421, 431, and 441 are coupled to each other within coordination server401, and may execute on one or more shared processors (not shown)coupled with memory (not shown). Coordination server 401 may include areal-time operating system, such as a Linux operating system, and mayinclude an operating system that distributes tasks among multiple cores.Coordination server 401 may provide one or more of modules 411, 421,431, 441 as processes, threads, user-mode or kernel-mode processes,processes in hardware or in software, in some embodiments. In someembodiments, each of modules 411, 421, 431, 441 may execute on the samecoordination server 401; in other embodiments, these modules may executeon remote machines connected via a network. In some embodiments, aremote failover coordination server (not shown) may be made availablefor handling failures at coordination server 401. The failover mechanismmay involve checkpointing operations at coordination server 401 in eachof the modules therein. Certain operations may be hardware accelerated,such as network processing tasks, IPsec tasks, deep packet inspectiontasks, or other tasks.

Coordination server 401 may include one or more network interfaces;these network interfaces may include Ethernet (10/100/1000/10000 Mbit)interfaces, Wi-Fi (802.11a/b/g/n/ac/af/ad) interfaces, 3G or 4Ginterfaces, virtual interfaces, or other interfaces. In someembodiments, one network interface may be directed towards the corenetwork and located at, or coupled to, EPC module 421; this interfacewould communicate using the Si protocol to MME 404 and using the X2protocol to macro cells 405, 406. In some embodiments, another networkinterface may be directed towards one or more RANs internal to thegateway and connected to RAN module 431, for communicating to RANs 402,using either S1 or X2 as appropriate. Translation or interworking ofprotocols may occur at one or more of modules 411, 421, 431, or 441 asappropriate. In some embodiments, SON module 411 may also be coupled toan interface for communicating with RANs 402, 403; this interface may belabeled the SON interface, and the NETCONF protocol (XML over HTTPS) maybe used to communicate in a proprietary or non-proprietary manner withRANs 402, 403 regarding network configuration, orchestration, andcoordination operations.

In particular, in some embodiments, coordination server 401 may performX2 brokering between eNodeB 402 and eNodeB 403 and other macro cells andthe core network. For example, if an HII message is requested to be sentby eNodeB 402, it may be sent to coordination server 401, which may thensend it to all other eNodeBs that require it, such as a macro cell oreNodeB 403.

Coordination server 401 may also, in some embodiments, handle schedulingand ICIC responsibilities in conjunction with eNodeBs 402 and 403. Forexample, coordination server 401 may communicate load or interferenceinformation from anywhere in the network to each eNodeB it is connectedto, including information among eNodeBs. Coordination server 401 mayalso communicate resource reservations. In some embodiments,coordination server 401 may share scheduling responsibilities, and theseresponsibilities may be divided between the nodes.

Various further embodiments are contemplated as well. In someembodiments, once the UE completes its emergency call, the servingeNodeB or the UE itself may inform the coordinating node, and thecoordinating node may then notify the set of related eNodeBs so that theassociated PRBs may be rescheduled for use by any attached UE'ssubsequent uplink transmission.

In some embodiments, without HII notification from a coordinating node,the related eNodeBs can also use other schemes, like uplink spectrumpower spectral density (PSD) sniffing solutions, to sniff the availableuplink spectrum (safe to use) and only assign these (un-used) uplinkPRBs.

In some embodiments, high-power transmission may be enabled via aself-organizing network (SON), X2 protocol communication, and/or radiofrequency sniffing to identify interference or the lack thereof using aradio antenna and module at the base station, or via UE measurementreports.

In some embodiments, an overload indicator (OI) may also be transmitted.

In some embodiments, the coordination may be performed directly amongnodes; in other embodiments it may be via a coordinating node.

In some embodiments, time blocks as well as resource blocks or frequencyblocks may be blocked out using an HII message. In some embodiments,eICIC messages may be used in conjunction to or in place of the ICICmessages described herein. In some embodiments, eICIC may be used inconjunction with LTE-Advanced. In some embodiments, some scheduling maytake place at a remote baseband location.

In some embodiments, high power may be requested by the base station tothe UE. In other embodiments, the UE may request high power. In someembodiments, the UE may be given a specific power at which to transmit,and the specific power may be determined based on neighboring radiosignal and interference conditions. In other embodiments, the UE may betold to use its maximum transmit power. In some embodiments, a powercontrol message according to the LTE protocol may be used by the basestation to request higher power from the UE.

In some embodiments, radio frequency signal in the vicinity of the UEand/or the base station may be considered, either using measurementreports, in some cases solicited from the UE, or using sniffing from thebase station, or another means. In some embodiments, one or more of thefollowing parameters may be used to evaluate radio frequency signal:received signal strength indication (RSSI), energy per bit to noisepower spectral density (Eb/N0), signal-to-noise ratio (SNR), referencesignal received power (RSRP), reference signal received quality (RSRQ),or any other parameters. In some embodiments, penetration loss may beincorporated into a determination of whether a high-power UEtransmission is needed. In some embodiments, measurements of penetrationmay be used to develop a model for penetration loss therefor. In someembodiments, a base station may solicit a UE to perform high-power UEtransmission.

In the present disclosure, the words “eNodeB” or “eNodeB” are used torefer to a cellular base station. However, one of skill in the art wouldappreciate that it would be possible to provide the same functionalityand services to other types of base stations, specifically to homeeNodeBs (HeNodeBs) and nodeBs, as well as any equivalents.

In the present disclosure, the words “federated,” “virtualized,” “proxy”or “proxied” may be viewed as aspects of the same concept. For example,it may be understood that the federated X2 gateway provides X2virtualization, in that it federates X2 messages from a plurality ofeNodeBs and virtualizes the plurality of eNodeBs to provide a singlevirtualized eNodeB. The X2 gateway provides this federation orvirtualization at least in part by providing proxy functionality, suchthat X2 messages from each of the plurality of eNodeBs may be proxied bythe X2 gateway to and from an EPC or core network node. Other meaningswould be apparent to one having ordinary skill in the relevanttechnology area. The X2 gateway could be part of an LTE accesscontroller or core network node, part of an eNodeB, co-located withanother device, or on its own independent device.

While the present disclosure uses the term “small cell,” this term isused merely to illustrate the concepts herein, and nothing is impliedregarding size, power level etc. for any cells that could be used withthe disclosed systems and methods, i.e. “small cell” may be interpretedas including macro cells, femto cells, multi-radio access technology(RAT) access nodes, indoor cells, outdoor cells, etc.

Various alternative embodiments are also contemplated by the inventors.For example, certain functions may be performed at an eNodeB, or at amulti-radio access technology node (multi-RAT) node, instead of at avirtualization server. The virtualization server may be known as an LTEaccess controller. The functions of the virtualization server may bebroken up and spread across multiple network nodes, or multiple softwareor hardware modules within the same network node, and may be physicallylocated in a single location, or multiple locations. The network nodemay be in the data path located between the radio access network (RAN)and the core network, in some embodiments, or may be located at anotherlocation in the network. A high-bandwidth wired connection may be usedfor backhaul, such as coaxial cable, fiber optic cable, or Ethernet, ora reduced-bandwidth wireless connection, such as microwave,line-of-sight, or other physical connections may be used as backhaul.

The protocols described herein may be optimized for greater or lesserlatency, for more or fewer mesh nodes, for more or fewer data streams,and other alternatives. In some embodiments, these optimizations may beperformed at the eNodeB, at the virtualization server, within a functionperforming radio resource allocation and coding selection, or at anotherlocation. In some embodiments, a virtualization server may identify andinitiate power adjustments to improve channel quality.

In some embodiments, the mesh network nodes may provide complete orpartial guesses at what paths are the optimal or best paths during aparticular time interval, and may be enabled to send messages back tothe virtualization server to communicate these complete or partialguesses.

In some embodiments, the base stations described herein may becompatible with a Long Term Evolution (LTE) radio transmission protocolor air interface. The LTE-compatible base stations may be eNodeBs. Inaddition to supporting the LTE protocol, the base stations may alsosupport other air interfaces, such as UMTS/HSPA, CDMA/CDMA2000,GSM/EDGE, GPRS, EVDO, other 3G/2G, legacy TDD, or other air interfacesused for mobile telephony. In some embodiments, the base stationsdescribed herein may support Wi-Fi air interfaces, which may include oneof 802.11a/b/g/n/ac/ad/af/ah. In some embodiments, the base stationsdescribed herein may support 802.16 (WiMAX), or other air interfaces. Insome embodiments, the base stations described herein may provide accessto land mobile radio (LMR)-associated radio frequency bands. In someembodiments, the base stations described herein may also support morethan one of the above radio frequency protocols, and may also supporttransmit power adjustments for some or all of the radio frequencyprotocols supported.

The foregoing discussion discloses and describes merely exemplaryembodiments of the present invention. In some embodiments, softwarethat, when executed, causes a device to perform the methods describedherein may be stored on a computer-readable medium such as a computermemory storage device, a hard disk, a flash drive, an optical disc, orthe like. As will be understood by those skilled in the art, the presentinvention may be embodied in other specific forms without departing fromthe spirit or essential characteristics thereof. For example, wirelessnetwork topology can also apply to wired networks, optical networks, andthe like. The methods may apply to LTE-compatible networks, toUMTS-compatible networks, or to networks for additional protocols thatutilize radio frequency data transmission. Various components in thedevices described herein may be added, removed, or substituted withthose having the same or similar functionality. Various steps asdescribed in the figures and specification may be added or removed fromthe processes described herein, and the steps described may be performedin an alternative order, consistent with the spirit of the invention.Accordingly, the disclosure of the present invention is intended to beillustrative of, but not limiting of, the scope of the invention, whichis specified in the following claims.

1. A method, comprising: receiving, at a base station, an emergencyrequest from a mobile device; coordinating a resource allocation with aself-organizing network (SON) module located at a coordinating node, thecoordinating node being an X2 aggregation point; sending, from the basestation to a neighboring base station, a scheduling hint to reserve oneor more radio resource blocks at a scheduler located at the neighboringbase station for non-use; and sending, from the base station to themobile device, a resource allocation including the one or more radioresource blocks and a power control message requesting high transmitpower.
 2. The method of claim 1, further comprising identifying whetherthe emergency request is an emergency call request or indicatesemergency status.
 3. The method of claim 1, further comprisingidentifying radio resources based on usage of radio resources by nearbymobile devices, nearby base stations, or both.
 4. The method of claim 1,further comprising coordinating scheduling with the scheduler located atthe neighboring base station via a scheduler located at the coordinatingnode via an X2 protocol message.
 5. The method of claim 1, wherein thebase station is an eNodeB, and the mobile device is a user equipment(UE).
 6. The method of claim 1, wherein the scheduling hint comprises aHigh Interference Indicator (HII) message and a Relative NarrowbandTransmit Power (RNTP) message.
 7. The method of claim 1, wherein theemergency request is an emergency attach request without user equipmentdevice authentication.
 8. The method of claim 1, wherein the emergencyrequest is a request to make an emergency call.
 9. The method of claim1, wherein the power control message identifies the one or more radioresource blocks.
 10. The method of claim 1, wherein the one or moreradio resource blocks are resource blocks designated by frequency ortime.
 11. The method of claim 1, wherein the mobile device is directedto use its maximum transmit power for uplink transmission to the basestation.
 12. The method of claim 1, wherein the base station uses ahigher transmit power for downlink transmission to the mobile device.13. A base station, comprising: a processing module for providingwireless communications to mobile users; a core network interfacecoupled to the processing module and in communication with a corenetwork; and an access interface coupled to the processing module, incommunication with one or more mobile devices, and capable of being usedfor emergency communications by the one or more mobile devices; whereinthe processing module is configured to: receive, at the base station, anemergency request from a mobile device; coordinate a resource allocationwith a self-organizing network (SON) module located at a coordinatingnode, the coordinating node being an X2 aggregation point; send, fromthe base station to a neighboring base station, a scheduling hint toreserve one or more radio resource blocks at a scheduler located at theneighboring base station for non-use; and send, from the base station tothe mobile device, a resource allocation including the one or more radioresource blocks and a power control message requesting high transmitpower.
 14. The base station of claim 13, wherein the base station is aneNodeB, and the mobile device is a user equipment (UE).
 15. The basestation of claim 13, wherein the scheduling hint comprises a HighInterference Indicator (HII) message and a Relative Narrowband TransmitPower (RNTP) message.
 16. The base station of claim 13, wherein theemergency request is an emergency attach request without user equipmentdevice authentication.
 17. The base station of claim 13, wherein theemergency request is a request to make an emergency call.
 18. The basestation of claim 13, wherein the power control message identifies theone or more radio resource blocks.
 19. The base station of claim 13,wherein the one or more radio resource blocks are resource blocksdesignated by frequency or time.
 20. The base station of claim 13,wherein the mobile device is directed to use its maximum transmit powerfor uplink transmission to the base station.